1. Field
The present invention generally relates to telecommunication conferencing, and more particularly to a method and system for combined P2P and central relay server-based telecommunication conferencing using a telephony and conferencing protocol.
2. Description of the Related Art
The common conferencing approaches mainly are traditional telephony/video conferencing and Peer-two-peer (P2P) conferencing.
In traditional telephony/video conferencing, an end-user sends a stream of media packets to a central relay, which collects those streams from multiple users and mixes them into a single stream, sending it for each of the participants. On another hand, in a P2P conferencing (e.g. Tokbox®), each participant directly sends their media to each of the conference participants, and the merging of the media is done on the end device of the user.
Each approach has its benefit (e.g. multiple video streams cannot be easily mixed, while audio can; clients located closely to each other can achieve better quality by sending media P2P, central relay doing mixing can save CPU and bandwidth for each client). But there are also mixed telecommunications conferencing system, where multiple clients participate in conferencing (e.g. audio and/or video) and client devices can either send media streams P-2-P or via a central relay, which mixes media streams received from different clients and sends the mixed stream to each client. With this combined P2P and central relay server approach, the telecommunication conferencing systems can optimize the bandwidth and processing power requirements on the terminals.
Patent US 2013/0028115 A1 describes one of such teleconferencing systems combining P2P and server-based conferencing. The terminals communicate conferencing content via peer-to-peer communication, directly between terminals that are members of the group of terminals, and using the selected coding scheme, and communicate the same conferencing content with other terminals participating in the conferencing call via at least one network device such as a conferencing-server and a peer-server.
The cited patent considers call quality as the only criteria for decision between using P2P or server based conferencing. However, there is a need for a method and a more flexible system capable of mixing server-based and P2P conferencing streams on the basis of other additional technical parameters not directly related to (affecting) the effective bit-rate available to the terminal, such as geographic location, user defined policies, network reachability (firewall traversal), etc.